Renesas 71V321L25PFGI

Overview

71V321L25PFGI from Renesas Electronics (formerly IDT) is a high-speed, 3.3V, 2K × 8 dual-port static RAM with on-chip interrupt logic and BUSY arbitration for interprocessor communication. It delivers 25 ns max access time, supports independent asynchronous reads/writes on left/right ports, and operates across –40°C to +85°C industrial temperature range in a 64-pin TQFP package. It is used in real-time embedded systems requiring concurrent memory access between two processors or DMA engines.

For engineers reviewing the 71V321L25PFGI datasheet, 71V321L25PFGI pinout, 71V321L25PFGI application, or 71V321L25PFGI equivalent, key selection criteria include dual-port arbitration timing (tBDD ≤ 45 ns), low-power standby current (ISB3 = 0.2 mA typ.), battery-backed data retention at 2V, and TTL-compatible 3.3V I/O with totem-pole BUSY/INT outputs.

Technical Context

The 71V321L25PFGI implements fully asynchronous dual-port architecture with separate address, control, and bidirectional I/O buses per port. Its on-chip arbitration logic uses address and chip-enable signals-not R/W state-to detect contention and assert BUSYL/BUSYR outputs without external logic.

Interrupt functionality is implemented via dedicated mailbox addresses (7FEh for INTL, 7FFh for INTR), where write operations from one port set the opposite port's flag, and read operations clear it. All timing parameters-including tINS/tINR (≤45 ns), tBAA/tBDA (≤30 ns), and tWDD/tDDD (≤80/65 ns)-are specified over full industrial temperature and 3.3V ±0.3V supply.

Key Specifications

Pinout & Package

71V321L25PFGI is housed in a 64-pin Thin Quad Flatpack (TQFP) with exposed thermal pad (PNG64). Pin functions are symmetrically distributed for left (L) and right (R) ports, supporting identical interface design on both sides.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-port SRAM applications.

Compared with CY7C136-25ZXC and AS7C3256B-25JCIN, the 71V321L25PFGI uniquely integrates hardware arbitration and interrupt mailbox logic in a single 3.3V device-reducing component count, PCB area, and firmware complexity for true interprocessor communication.

Availability

71V321L25PFGI is available at Aetrix Electronics and suitable for industrial motion controllers, avionics display systems, and medical imaging equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 71V321L25PFGI includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Renesas Electronics Corporation is a global semiconductor leader delivering microcontrollers, analog, power, and memory solutions for automotive, industrial, and infrastructure markets.

The 71V321L25PFGI belongs to Renesas' legacy dual-port SRAM portfolio-originally developed by IDT-to enable deterministic, low-latency interprocessor communication in real-time embedded systems without software overhead.

FAQ

What is the maximum operating frequency supported by the 71V321L25PFGI?

The 71V321L25PFGI has a 25 ns maximum access time (tAA), supporting effective bus clock rates up to 40 MHz in zero-wait-state configurations. Its read cycle time (tRC) is also 25 ns, and all AC timing parameters-including tBAA, tINS, and tWDD-are guaranteed across –40°C to +85°C at 3.3V ±0.3V. The device does not require an external clock; operation is fully asynchronous per port.

Does the 71V321L25PFGI require external pull-up resistors on BUSY or INT pins?

No. The 71V321L25PFGI features totem-pole output drivers on BUSYL, BUSYR, INTL, and INTR pins-confirmed in the datasheet notes and functional block diagram. These outputs drive actively high or low without external passive components, simplifying layout and reducing bill-of-materials cost compared to open-drain alternatives.

How does the 71V321L25PFGI handle memory contention between ports?

The 71V321L25PFGI uses hardware-based address-and-CE arbitration: when both ports access the same address simultaneously, BUSYL or BUSYR asserts within 30 ns (tBAA max), and the write signal on the contending port is gated internally-preventing invalid data writes. No software intervention or external logic is required, and the winning port proceeds without delay.

Can the 71V321L25PFGI retain data during power loss?

Yes. The "L" suffix denotes low-power capability, including guaranteed data retention at VCC ≥ 2.0 V. In retention mode (CE held high, VCC = 2.0 V), ICCDR is ≤ 500 µA typical, allowing integration with coin-cell or supercapacitor backup. This is validated per datasheet Table 7 and Figure 4 (Data Retention Waveform).

What package and lead finish does the 71V321L25PFGI use?

The 71V321L25PFGI uses a 64-pin TQFP (Thin Quad Flatpack) package coded PNG64, measuring 10 mm × 10 mm × 1.4 mm. It features lead-free (RoHS-compliant), green-variant construction-confirmed in the Ordering Information table and Package Code definitions on page 14 of the datasheet.